Atomic-precision multilayer coating of the first set of optics for an extreme-ultraviolet lithography prototype system
Abstract
We present our results of coating a first set of optical elements for an extreme-ultraviolet (EUV) lithography system. The optics were coated with Mo-Si multilayer mirrors by dc magnetron sputtering and characterized by synchrotron radiation. Near-normal incidence reflectances above 65% were achieved at 13.35 nm. The run-to-run reproducibility of the reflectance peak wavelength was maintained to within 0.4%, and the thickness uniformity (or gradient) was controlled to within plus-or-minus0.05% peak to valley, exceeding the prescribed specification. The deposition technique used for this study is an enabling technology for EUV lithography, making it possible to fabricate multilayer-coated optics to accuracies commensurate with atomic dimensions.
- Publication:
-
Applied Optics
- Pub Date:
- June 2002
- DOI:
- 10.1364/AO.41.003262
- Bibcode:
- 2002ApOpt..41.3262M
- Keywords:
-
- Extreme Ultraviolet Radiation;
- Lithography;
- Optical Materials;
- Reflectance;
- Sputtering;
- Ultraviolet Radiation;
- Optics